123817643 has 2 divisors, whose sum is σ = 123817644. Its totient is φ = 123817642.

The previous prime is 123817637. The next prime is 123817669. The reversal of 123817643 is 346718321.

It is a weak prime.

It is an emirp because it is prime and its reverse (346718321) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 123817643 - 2¹⁶ = 123752107 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (123817843) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61908821 + 61908822.

It is an arithmetic number, because the mean of its divisors is an integer number (61908822).

Almost surely, 2^123817643 is an apocalyptic number.

123817643 is a deficient number, since it is larger than the sum of its proper divisors (1).

123817643 is an equidigital number, since it uses as much as digits as its factorization.

123817643 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 24192, while the sum is 35.

The square root of 123817643 is about 11127.3376420418. The cubic root of 123817643 is about 498.4185271611.

It can be divided in two parts, 1238 and 17643, that added together give a palindrome (18881).

The spelling of 123817643 in words is "one hundred twenty-three million, eight hundred seventeen thousand, six hundred forty-three".